From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH net-next] mlx4: change TX coalescing defaults
Date: Wed, 07 Nov 2012 15:31:13 -0500 (EST)
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From: Eric Dumazet <eric.dumazet@gmail.com>
Date: Mon, 05 Nov 2012 18:20:42 -0800

> From: Eric Dumazet <edumazet@google.com>
> 
> mlx4 currently uses a too high tx coalescing setting, deferring
> TX completion interrupts by up to 128 us.
> 
> With the recent skb_orphan() removal in commit 8112ec3b872,
> performance of a single TCP flow is capped to ~4 Gbps, unless
> we increase tcp_limit_output_bytes.
> 
> I suggest using 16 us instead of 128 us, allowing a finer control.
> 
> Performance of a single TCP flow is restored to previous levels,
> while keeping TCP small queues fully enabled with default sysctl.
> 
> This patch is also a BQL prereq.
> 
> Reported-by: Vimalkumar <j.vimal@gmail.com>
> Signed-off-by: Eric Dumazet <edumazet@google.com>

Applied, thanks Eric.